MINE VENTILATION
than their equivalent diesel engines. The diesel
engine efficiency is typically around 33%, while
electric motors are typically around 95% efficient.
However, it is important to bear in mind that the
ventilation requirements for a battery-electric
mine does not completely follow the same
electric-diesel efficiency ratio.”
A mixed bag
For all the talk of electric-powered machines
coming into the underground mining space, the
reality today is that fleets are still made up of both
diesel and electric equipment – the former
outweighing the latter.
The same is the case for automation and
teleremote operations, with different mines having
more automation than others. This diversity of
operator can also be seen within one mine itself
as certain areas of manned mines are cordoned off
for autonomous-only work.
It is such diversity that requires a sophisticated
mine ventilation distribution and monitoring system.
“You will have mixed fleets for a long time –
both diesel and electric vehicles will be there,”
Nyqvist said. “That provides the opportunity to
distribute the air depending on where the different
vehicles are. As a result, I see a bigger need in the
future for a good, sophisticated ventilation system.”
The ability to integrate with tagging, tracking
and dispatch systems from mining equipment will
be pre-requisites for these mine ventilation and
monitoring systems.
Ouimet, referencing SHYFTinc’s own NRG1-ECO
energy management solution, provided an
example.
“Our system can recognise the size of engine
on each machine, as well as what it is discharging
into the stopes,” he said. “You can do that by
using the machine tracking analytics, or through
the environmental air quality monitoring station.”
In transition
According to Dello Sbarba, Howden was quick to
realise the industry was moving towards a future
where ventilation control, not ventilation volume,
is becoming the most important criteria.
“This is why Howden bought Simsmart, who
are leaders in ventilation on demand (VoD)
systems,” he told IM. “We saw this shift in the
industry and were proactive in realising that we
had to offer not only the steel (fans) to our clients,
but the full solution.”
The addition of Ventsim from Chasm Consulting
in 2017 enabled the company to use the model as
a tool to improve and test the controls
implemented where Ventsim CONTROL was born.
The model gives the company the ability to
understand and predict how the controls will react
in any situation whether it is for emergencies,
blast clearing, excessive contaminants, cooling
etc, Howden says.
“There is definitely a shift in the market and
that is being catered for with our total mine
ventilation solution strategy where we offer full
turnkey ventilation solutions from the mine
engineering all the way through to the equipment
supply of fans, cooling systems, heaters and, of
course, the controls and all of the instrumentation
that comes with that,” Dello Sbarba explained.
Other companies in the ventilation field were
also prepared for this transition, one such firm
being Maestro.
Maestro’s market ambitions are far greater than
the mine ventilation space, as Gribbons points out.
He told IM: “While we started in the ventilation
field, our domain expertise remains in the IIoT
(Industrial Internet of Things) and digital
networking space.”
Despite this, Maestro has gained a reputation
for providing ventilation control and environmental
monitoring solutions that are ready to cope with
the diversities of today’s and tomorrow’s
underground mines.
This is backed up by the fact its Vigilante AQS™
(air quality station), which was introduced less
than eight years ago, is in use at over 135
operations in 27 countries. Last year, it increased
that market penetration with the introduction of
its Zephyr AQS™ product.
Both are compact, environmental AQSs for
underground mines, but Vigilante is seen as a
holistic solution that can solve 100% of the
applications for mine ventilation monitoring and
control. Zephyr, meanwhile, is designed for 75% of
the applications – such as airflow rate, airflow
direction, gas levels, barometric pressure, and
wet/dry bulb temperatures.
Gribbons and Maestro expected to capture the
mid-tier and smaller mine operators with the
introduction of Zephyr but, a year after launch,
both have been surprised by the market uptake.
“Originally, we thought it would be a hit in
Africa and Latin America, but when it was
launched, it opened up applications with both our
existing mining clients and those that could not
originally afford the Vigilante AQS,” Gribbons said.
Large global miners like Vale, Rio Tinto, Barrick
Gold and Newmont all saw the
value in bolting on a Zephyr unit
to their existing mine
infrastructure, realising it could
be easily integrated with other
Vigilante units and could be
funded through their existing
budgets.
In terms of ventilation and
environmental monitoring
requirements, Gribbons sees
steady demand from the mining
market, even with the increasing take-up of
battery-electric equipment.
“We have witnessed as many environmental
monitoring stations in all-electric mines as we do
in regular mines,” he said, referencing the
company’s work with Borden specifically.
But Gribbons does see changes coming, which
Maestro is prepared for.
“With the on-coming electrification of mobile
fleets, the next additional environmental or
ventilation constraint will be dust,” he said.
This belief has led the company to invest R&D
dollars in a new compact dust sensor that can
monitor both the dust particulate matter (PM) size
and the dust loading, satisfying regulatory and
worker safety concerns.
“We are currently Beta testing the new
DustMon PM sensor at a Vale mine now. The new
sensor can be added to any existing Vigilante or
Zephyr AQS similar to that of our gas sensors,” he
said. “It is an economical, plug and play, IIoT
device.”
Gribbons says an air sample is drawn through
the sensor and a laser counts the PM and groups
the particles by size.
“The on-going testing will provide data on how
often the sensor will need to be serviced in a
dusty ramp application,” Gribbons said. “We expect
this to go into full production by September or
October 2020 if no further modifications are
required from a mechanical standpoint.”
Powering up
Maestro’s R&D does not end there.
Its Vigilante AQS is also being revamped to
cope with increased requirements from mining
companies, Gribbons said.
“After clients began to implement our Vigilante
stations, they would often come back to us with
new ideas,” he said. “At a certain point in time,
the horsepower under the hood could not cope
with all of these new applications and ideas.”
Ballantyne expanded on this: “We’re going to
use that increased horsepower to improve the
number of different communication protocols we
can support.
“We have basically rethought how we will
configure standard, generic type input/output
applications with it.”
Maestro’s Vigilante AQS is in use at operations
owned by 17 of the top 20 mining companies in
the world
86 International Mining | JULY/AUGUST 2020